


Wiped From the Stars

by ProphecyGirl



Category: Supergirl (TV 2015), The 100 (TV)
Genre: A.L.I.E. - Freeform, ALIE - Freeform, Alternate Universe - Canon Divergence, Canon Compliant, CatCo Worldwide Media, City of Light (The 100), Crossover, Gen, Hive Mind, I Don't Even Know, I Tried, I Wrote This Instead of Sleeping, I'm Sorry, Krypton, Kryptonian Biology, Kryptonite, Multiverse, Myriad Program (Supergirl), Post-Episode: s01e19 Myriad
Language: English
Status: Completed
Published: 2019-05-28
Updated: 2019-05-28
Packaged: 2020-03-26 12:14:27
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,943
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19005583
Author URL: https://archiveofourown.org/users/ProphecyGirl/pseuds/ProphecyGirl
Summary: Kara gets some very unexpected help defeating Myriad from someone who understands all too well how it works.





	Wiped From the Stars

**Author's Note:**

> This is for cTine, Luna, and Lewlew—I love you, Trashkru.
> 
> Everyone else: This is my first crossover, my first Supergirl fic, and my first experience with multiverse theory, so it's probably a dumpsterfire and you should all feel free to blame above-mentioned Trashkru for the fact that this exists at all. It's definitely their fault.

_"Everything was just wiped from the stars." - Kara Danvers/Supergirl, 'Myriad'_

 

Kara had felt alone most of her life, from the moment she'd started her journey to Earth. But as she watched her coworkers, her friends, staring with unseeing eyes, she realized she'd had no idea what loneliness truly was until now. She had no idea what to do and was nearly at the point of falling apart when the elevator bell dinged. Kara jerked her head towards it as the doors opened.

She didn't know what or who she was expecting, but it definitely wasn't an unfamiliar blonde girl in threadbare clothes, wearing several pieces of worn, strange-looking armor. As she stepped out of the elevator, it was immediately apparent that whatever was causing people to become zombies hadn't affected her. Her eyes quickly scanned the room and landed on Kara, bringing a grim smile to her lips as she raised a radio that looked like it had been assembled from garbage and spoke into it.

"I found her."

Kara stood, an uncomfortable feeling in the pit of her stomach as she wondered what fresh hell was approaching. As the girl came closer, Kara suddenly felt slightly dizzy, her stomach starting to churn a bit.

"Kara Danvers, we've been looking everywhere for you." The girl was only an arm's reach away from where Kara was leaning on Winn's desk, trying to steady herself against the feeling she recognized a little too well.

A wave of weakness taking over her body, Kara stifled a groan as she gripped the desk harder. "How do you know my name?"

"I know a lot about you, Kara. I'm sorry for this." The girl pulled out a small, cylindrical device that was radiating a familiar, bright green light. Kara swayed under the effects of the Kryptonite emitter and collapsed on the floor. The girl knelt beside her, setting the emitter down, and taking out a pair of cuffs that she slapped on Kara's wrists.

"I don't want to hurt you, just suppress your powers for now, until we've had a chance to talk."

"Start talking then," Kara snapped.

The girl shook her head. "We can't here. It's not safe. This place is full of computers."

"What does that have to do with anyt—" Kara cut herself off as the elevator dinged once more. It opened, and a guy in similar tattered clothes stepped off it and headed toward them. "Who are you people? What are you doing?"

He leaned over and easily scooped Kara up. "Are you sure this is really necessary? We could have just _asked_ her to come with us."

"We can't risk her saying no. You know that, Bellamy."

Kara was finding it nearly impossible to talk, and as she found the blonde's eyes she tried to ask who they were once more, but it came out nothing more than incoherent babbling. The blonde's face was stone, expressionless, as she gazed back at Kara and turned the dial on the stick up a little further.

"I really am sorry about this, Kara," she said calmly. "I promise we aren't here to hurt you, or anyone else."

Kara mustered what little strength she had left, still looking at the blonde as the man began carrying her to the elevator.

"Who are you?" She asked again hoarsely.

The girl hit a button on the elevator wall and turned to Kara again as the doors shut.

"My name is Clarke. Clarke Griffin. And I need you to help me save the world."

* * *

 

"Raven, your modified reaper stick worked perfectly. We got her and we're almost home."

Clarke clipped her radio back in place and revved the motorbike as she swerved around all the cars that had been abandoned when the hive-mind kicked on. She glanced over at Bellamy, who had a nearly unconscious Supergirl—Kara, she meant—slumped between his body and the handlebars. He revved back with a short nod to let her know he was good.

The transport ship waited just ahead, looking totally out of place on the football field Raven had set it down in. Clarke sped up and Bellamy fell in line behind her as they drove right up the ramp and into the ship. Octavia and Murphy were already back from checking Kara's apartment and rushed to help Bellamy get her off the bike and onto a stretcher.

Clarke hit the button on the wall. "Raven, we're all home. Get us outta here."

"Everyone buckle up, we're go for liftoff in 20," came the response from Raven over the loudspeaker as the ramp began to lift.

Clarke turned to face the others. "Get her down to medical, now, and let me know when she's ready for me." She tossed the Kryptonite stick to Bellamy and headed through the airlock to the bridge as the ramp sealed closed.

"Liftoff in five, four, three, two.." Raven's voice counted down as the ship began to shudder and shake, the thrusters firing off and forcing it off the ground.

Kara's eyes darted around in fear and confusion as she was quickly moved down a hallway, her chest tightening from the prolonged exposure to the Kryptonite. She finally came to a stop under uncomfortably bright lights, a woman about her mom's age walking up beside her. "Is Clarke—?

"She's fine, Abby," Murphy replied.

The woman—Abby—leaned over her a little. "Kara, I'm sorry for this. I promise, Clarke will explain everything."

Kara gasped quietly when she felt the sharp pinch of a needle in her neck. Her head quickly grew heavy, and she felt incapable of preventing her eyelids from closing. Everything around her blurred and softened, and she felt like she was floating gently away as she slipped quietly into unconsciousness.

* * *

 

When Kara woke, she no longer felt the sickening weakness Kryptonite caused, and her arms weren't cuffed anymore. It took her a minute to remember what was going on and she immediately tried to get up only to find that she couldn't move, at all.

"It's a paralytic." Kara turned towards the voice to see the face of the blonde from earlier. Clarke. She was using the tip of a small knife to clean under her fingernails, and paused to look at her. "I need you to believe every word I'm about to say. I thought the most efficient way to ensure that would be to show you that, if I were looking to hurt you or kill you, I could. We have technology your Earth hasn't even dreamed of yet. More than enough power to take out Supergirl, National City, and the entire planet. We've got some experience in this area."

Kara was able to move her eyes, and they scanned the landscape quickly, but found nothing remarkable about wherever she was, much less anything inspiring a good escape plan.

Clarke leaned forward a little. "Blink once for yes, twice for no. Have you heard of Myriad, Kara?" Kara's eyes quickly returned to Clarke, her pupils dilating slightly as she blinked. "Good. Do you know what it is?" Two blinks.

"It's an altered version of an artificial intelligence program called ALIE. It's a really long story, but the short version is that the ALIE code destroyed my earth and enslaved most of my people. We were able to stop it and free everyone's minds. We thought it was over. Then Raven, our resident tech genius, found something weird in ALIE's code. Somehow, ALIE figured out the vibration rates at which a handful of other Earths exist, and she learned how to jump between them."

Kara didn't think that she could have spoken at that moment even if she wasn't paralyzed. Nothing Clarke was saying made sense, but at the same time, it made complete sense.

"Each of those Earths now have an altered ALIE code, and here on your Earth it's called Myriad."

Kara felt her muscles starting to loosen up as the paralytic began wearing off. Clarke, to her credit, merely rested her arms on the back of the chair she was sitting backwards in as Kara slowly sat up. She could feel not just the paralysis wearing off, but also her full powers and strength coming back.

"I should kick your ass for doing that to me, Clarke Griffin."

Clarke shrugged a little. "You can if you want to, but I think you'd rather go straight to the world-saving part."

Kara crossed her arms, mildly annoyed that this total stranger had her number to this degree. "What do you need from me?"

"Your mother's necklace."

Kara just looked at her with confusion, tugging the object in question out from beneath her top where she'd tucked it. "What? Why? How do you even know about that?"

Clarke put her hand out and Kara very reluctantly removed the necklace and placed it into Clarke's waiting hand. While Kara looked on nervously, Clarke carefully pried out the stone setting and held it up between two fingers so Kara could see it as well.

" _Ascende superius._ "

Kara watched in stunned horror as long spindles emerged from the stone, grasping the empty air for a moment before retracting back inside it again. "What the hell is that thing?"

"I don't know what it's called here," Clarke said, closing her hand around the stone. "The version in our world is called the Flame, or the Spirit of the Commanders. It's an AI chip that holds the minds of people who have had it in them. Not just a memory, but that person's.. Spirit, or essence, whatever you want to call it."

Kara felt dizzy again, but this time it had nothing to do with Kryptonite. "Wait, _in_ them? How.."

"In our world, there are people with black blood, we call it Nightblood. We're the only ones who are bio-compatible with the Flame. Without Nightblood, the Flame kills you. When a Nightblood takes it, it takes root in your brain and enhances it in certain ways, including allowing the other people whose minds are stored in the Flame, to speak to you." Clarke paused and took a breath when she saw how pale Kara looked. "I know all of this probably sounds crazy, even to a girl from another planet with super powers, but I promise you it's all real. ALIE is real, and she, or rather Myriad, I guess, is definitely a serious threat."

Kara rubbed her face, taking a deep breath to steady herself. "I know. I mean, it's already happening. Everyone is.. In a trance or something."

"That's why we have to move quickly. Their minds are somewhere else—on our planet, it was called the City of Light. I have to use the Flame to go in and find the kill switch."

Kara's face hardened a little as she studied Clarke. "Kill switch? What happens to all these people when you do that?"

"We don't know."

"You don't know?" Kara crossed her arms, standing up. "So they could all die?"

"Just the ones that have been taken. One city's worth of people, versus the entire world." Clarke's tone was much more casual than the tone of anyone suggesting mass murder had a right to be.

"No." Kara shook her head. "No way. There's gotta be another way, a way that doesn't kill everyone in the city limits."

Clarke stood as well, her hand closing tightly around the stone, or the flame, whatever it was. "Kara, we have no choice. If we don't do this, we can't destroy Myriad, and your people die anyway, along with the rest of the world."

"We _always_ have a choice, Clarke."

Clarke just shook her head a little sadly. "Not always."

* * *

 

"What do you mean, it won't work?" Clarke felt the beginnings of a serious headache starting to form.

Raven turned the monitor so Clarke could see the lab footage on the screen and they both watched in dismay as Kara's Flame brought the surrounding Nightblood to a rapid boil that consumed every drop of blood and left behind a deep scorch mark in its wake.

"It's not bio-compatible with Nightblood. I—I'm sorry, Clarke. It won't work."

Clarke slapped the wall with a frustrated groan.

Raven drummed her fingers on the table while watching the footage again, her brow furrowing a little.

Clarke paused. "I know that look. What are you thinking?"

Raven shook her head a little. "We'd have to test it first.."

"Test what?"

Raven swiveled around in her chair to face Clarke. "I need a sample of Kara's blood. This AI is from Krypton, right?"

"You think it's bio-compatible with Kryptonian blood." Clarke said slowly.

Raven nodded. "You said Kara hated this plan, though. Do you really think she'll go in and pull the kill switch if we can't guarantee the hive-mind will survive it?"

Clarke stared down at the stone chip, her voice quiet. "If she doesn't, her world dies."

* * *

 

"You're sure about this?" Kara watched as Clarke and Raven attached various electrodes and monitors to her.

Raven opened her mouth, but Clarke was the one who spoke. "Positive."

Raven let out a little puff of air and turned towards the console as readings began popping up. "Try to relax, Kara. I need to get some baseline readings before you take the Flame, so I can monitor you properly while you're in the City of Light."

Kara shifted a little, part of her in total disbelief that she was about to let these two strangers from another world shove a computer chip that might kill her into her brain so she could find a switch that would possibly kill everyone she knew. She felt pangs of guilt when she realized how grateful she was that Alex wasn't in National City.

_Maybe it will be okay. Maybe it won't kill everyone._

Raven hit a few keys before turning back around. "Are you ready, Kara?"

Kara took a deep, steadying breath, and nodded a little, then lowered her head as Clarke came close. She held up the Kryptonian Flame and brushed Kara's hair off the back of her neck. Kara shut her eyes tightly, bracing herself.

" _Ascende superius_."

After a brief moment, Kara felt the chip pierce the back of her neck, sending a shockwave of pain through her like she'd never felt before. She screamed and screamed until everything went black.

* * *

 

Kara opened her eyes as the searing pain suddenly disappeared, and found herself in the middle of the house she'd grown up in back on Krypton. Every detail was exactly as she remembered it, right down to the tinted spot on the floor where she'd spilled paint that they never could get totally clean.

She looked around in awe, reaching her hand out to run it lightly over a table. It all felt real, like she'd woken up from a long, strange dream that already seemed a billion light years away.

"Kara," came a familiar voice from behind her. "My dear Kara."

Kara's lower lip was already trembling when she turned around. "Mom?"

Alura put her arms out and Kara ran into them, clinging to her tightly. "I'm here, Kara."

Kara held onto her like she was a lifeboat in a storm. "I thought I'd never see you again."

"I'm always with you, Kara."

"So am I."

Kara saw Astra over her mother's shoulder and felt a fresh wave of tears building up behind her eyes. She reluctantly let go of Alura and flew into Astra's arms, her voice thick with emotion. "I'm so sorry for what happened, this isn't what I wanted."

"It's okay, little one. We have another chance, now." Astra pulled back a little and brushed Kara's hair off her face gently. "Now that you have the Flame, we can finish what I started and save Earth."

Kara pulled back slowly, her brows furrowing. "What you started? You're responsible for Myriad?"

"That's why I sent her to Fort Rozz. She tried to use it on Krypton," Alura took a step closer, giving her sister a dirty look.

Astra was firm, her voice confident. "Yes, I did. To _save_ Krypton."

"By putting everyone under mind control!"

Kara's head swiveled back and forth like she was watching a tennis match, her head throbbing. "Stop arguing, please! You have to help me find the kill switch."

Astra shook her head vehemently. "You can't do that, Kara. If you pull the kill switch, if you stop Myriad, everyone you know will die, and then everyone on the planet will, too. Myriad is what will save the Earth."

"Don't listen to her, Kara. You know what has to be done, and you know the consequences of it. Help me stop her from destroying this world, too."

Kara opened her mouth to speak, genuinely feeling like she was being physically pulled in different directions, when a squawk from behind her startled her. She turned around and saw a black bird that definitely didn't belong on Krypton, perched on the table.

"It's a raven," she murmured quietly, taking a tentative step towards it. The bird stared at her as she slowly approached, and when she got close, it lifted off into the air and flew out of the room, down the hallway. Astra and Alura called out to her as she took off after the bird.

Kara ran after the raven for what felt like forever, with her mother and aunt—or more accurately, the spirits of her mother and aunt, she thought—hot on her heels and calling out to her, but she didn't stop. She couldn't stop, despite the heavy feeling in the pit of her stomach at the thought of hitting the kill switch.

The faces of the people on Earth she cared for were haunting her mind as she ran. She tried to rationalize that if the world collapsed, they would die anyway, but that seemed like such an abstract concept compared to them dying because she pulled a lever that she already knew might kill them. Either way, she would have to live with the guilt of causing their deaths, and whether it was indirectly or directly didn't seem to make her feel any less shattered by it.

Kara followed the raven into an unfamiliar building, where it flew into a room that was the spitting image of Cat Grant's office. Kara skidded to a stop, thrown by this development. "How.."

Alura came in just a few strides ahead of her sister, touching Kara's shoulder gently. "Your mind is changing things, Kara."

Right in the center of Cat's desk was a large lever that was emitting a light blue glow.

"The kill switch," Kara said, mostly to herself, as the raven landed beside it and looked at her expectantly.

"You know what to do, Kara. Activate the switch, save your adoptive planet. Save your friends and your sister."

Astra caught up and put her body between Kara and the switch. "Kara, I'm begging you. Don't do this. You'll be signing the death warrant for the entire planet if you do. The humans will use up all the resources, they'll destroy it and everyone will die, including your friends and Alex."

Kara felt the weight of her emotions as she gazed between her mother, her aunt, and the damn bird that was hopping from one side of the desk to the other anxiously.

"This isn't who you are, Kara. You're not someone who would allow an entire species to be enslaved, and that's what Astra is doing."

Astra whirled on her sister angrily. "To _save_ them, Alura. You wouldn't listen to me when I was trying to save our own planet, and now it's gone and Kryptonians are all but extinct. You're making the same mistakes again, and pushing Kara to make them, too!"

"How can you think mind-control is the solution to anything, Astra? You've taken away their free will, their individualism, their feelings and memories. That's not your choice to make for them!"

"I'm making the choice to save them from themselves! From the destruction they rain down on their only planet, from the pain they cause themselves and each other! I am trying to _ease_ that pain!"

Kara shut her eyes for a moment, overwhelmed as the sisters' voices grew louder and even more argumentative, and she felt herself starting to shake a little before she finally snapped. She slammed her hands on the desk, and both women turned towards her once more.

Her voice was low and tense as she rested her hand on the kill switch lever, her jaw set.

"You don't ease pain. You overcome it." Kara slowly pulled the lever down, trying to focus on the proud expression on her mother's face rather than the one of betrayal on her aunt's. "And we will overcome it."

The lever clicked into place and Kara took a deep breath as the world around her melted into darkness.

* * *

 

This time, when Kara woke, she was back under the fluorescent lights with machines beeping all around her, watching through blurred eyes as a hand pulled away from her with the stone in it, the spider legs retracting back inside it once more.

"Kara? Kara, it's okay. Wake up."

Kara mumbled, disoriented. "Are they alive?"

Blonde hair came into view as her vision righted itself. "They're alive. Kara, you did it. You shut down Myriad, and your friends are fine."

Kara smiled sleepily as Clarke helped her sit up slowly. "James? Winn, Cat.. Alex? They're all okay?"

Raven turned a monitor around so Kara could see the confusion as everyone in the Catco office woke from their shared trance. "Alex was never part of the hive-mind. She's with your adoptive mother, and they're both safe. We're on our way there now to drop you off."

Raven took the Flame and was carefully reassembling it into the frame of Alura's necklace. Kara sat still on the table as Clarke worked on removing all the wires that were attached to her. "While I was in the Flame, my aunt told me Myriad was to save Earth, and if I shut it down, everyone here would die. Was that true?"

Clarke touched her arm affectionately. "It doesn't have to be. When we shut down ALIE in our world, we found out that she'd done all this because we were facing a total nuclear apocalypse in six months. We were just a bunch of juvenile delinquents with no special powers. If we found a way around that, I think Supergirl can probably do even better for this Earth. Especially now that you've got your friends back."

Kara returned the friendly, honest smile Clarke was giving her as the last of the electrodes came free.

"Thanks, Clarke." Kara put her hand out to shake hers, and there was a moment of awkwardness when Clarke grabbed her forearm instead, but Kara quickly realized what she was trying to do. They shook arms and Clarke nodded her approval as Raven brought the transport ship down in a park not far from the Danvers house.

Raven stood and Kara put her arm out for her as well, but instead of taking it, Raven just hugged her. Kara closed her eyes briefly, hugging her back for a moment before releasing her. Raven handed her back the necklace, which she immediately put back on, and she and Clarke walked Kara out of the airlock.

Kara glanced back just once as she headed out of the ship, fingering the necklace distractedly, and both girls were watching her with smiles.

It was Clarke who spoke, inclining her head toward Kara a bit. "May we meet again, Supergirl."

Kara smiled. "I hope we do."


End file.
